Biological invasions represent one of the most pervasive threats faced by aquatic ecosystems. However, we are still lacking a detailed, mechanistic understanding of how whole ecosystems may respond to biological invasions on the long term. This limitation, we believe, stems from (i) a relative paucity of experimental approaches in invasion biology, (ii) time and publication constraints urging researchers to favour short-term approaches, (iii) an overlook of the potential roles of rapid phenotypic changes on ecological interactions and (iv) the huge workforce needed to holistically measure eco-evolutionary dynamics at ecosystem scales. Here, we describe the inception of an experiment aiming at tackling issues through manipulating densities of the red swamp crayfish (Procambarus clarkii) in vegetated freshwater mesocosms. The twelve, 11 m2 mesocosms are designed for long-term use (up to 10 years) and are fully-dedicated to this experiment, thus securing the possibility for a long-term approach starting in 2022. We plan to track phenotypes and abundances in small- to large-sized organisms (phytobenthos, plankton, macroinvertebrates, macrophytes) using automated image analysis. To that aim, we have two FlowCams available (8000 and Macro), and we are developing novel tools for the automated analysis of macroinvertebrate videos and UAV images of primary producers. However, we are still facing a workforce bottleneck for the analysis of numerous samples (zooplankton), and the monitoring of microbes (viruses, bacteria, protists) and crucial aspects of ecosystem functioning (decomposition, metabolism). We are therefore looking for collaborators eager to participate in this long-term experiment in the context of Aquacosm+ and beyond.